A charging and relief valve such as illustrated in U.S. Pat. Application Ser. No. 757,263 provides for charging an accumulator and relieving the same as the pressure differential across the valve varies. As the relief valve is disposed within a casing of the charging valve portion, it is advantageous to construct the charging and relief valve as a single unitary assembly.
Moreover, during the construction of the charging and relief valve it is important to provide a valve seat which cooperates with the relief valve portion to prevent leakage through the relief valve below a predetermined pressure.